A group of prisoner and civil rights advocates is asking the U.S. Department of Justice to investigate solitary confinement practices in North Carolina prisons, saying the state has deployed a “dangerous and unconstitutional use of isolation.”

The request was made in a 15-page letter delivered Monday to the department’s Office of Civil Rights from six groups: the American Civil Liberties Union of North Carolina, the ACLU’s National Prison Project, North Carolina Prison Legal Services, the UNC School of Law Human Rights Policy Seminar, UNC’s Center for Civil Rights, and North Carolina Stop Torture Now.

But the groups say Kerr was not an isolated episode – that “such neglect is in fact routine for many inmates with mental illness” – and they include snapshots of details from four other inmates, who are not identified by name. Those cases are described as involving inmates with mental illnesses who are isolated, where their conditions deteriorate.

Never miss a local story.

Sign up today for a free 30 day free trial of unlimited digital access.

The letter says the prison system is “in crisis” after years of declining support for community mental health services that has turned the prisons into the “largest provider of mental health care in the state.”

State prison officials have previously acknowledged problems with the system’s use of segregated housing units and have pledged some changes.

The state’s Department of Public Safety said it has not received a copy of the letter or been contacted by the groups. Spokeswoman Pamela Walker said the agency welcomes outside scrutiny.

“Commissioner W. David Guice says that he is willing to work with any outside entity that wishes to conduct a review of the reforms and the new direction the agency is taking in regards to restrictive housing,” Walker said. “Adult Correction has already been working with outside entities ... to create new policy and procedures for behavior modification.”

Already, the state’s prison system is one of five nationwide now participating in a program intended to reduce the use of solitary confinement. The initiative, led by the Vera Institute of Justice, is trying to find alternatives, particularly in cases of segregation issued as punishment for disciplinary infractions.

Experts say there are better, more efficient ways to change inmate behavior than by sending an inmate to solitary confinement.

The advocates say the issue should be a concern to the public, too:

▪ More than 90 percent of inmates in North Carolina are released back into society. Of those, 31 percent are released straight from an isolated cell – the size of a parking space – into the community.

▪ Roughly 5,300 of the state’s 38,000 prisoners are segregated away from the regular prison population for 23 to 24 hours on any given day. Some are isolated because they are considered a threat to staff members and other inmates. A few are placed there because they are considered an escape risk.

But most are moved to solitary confinement as punishment for infractions – some as minor as using profanity.

▪ More than 1 in 5 prisoners in isolation should be receiving treatment for mental health issues, advocates say. They say the state’s handling of solitary confinement worsens the mental health concerns.

Chris Brook, legal director of the ACLU of North Carolina, said the state has had ample time to fix the concerns, but it has not.

“When you see these problems build up over a decade and proposed solutions don’t come to fruition or they don’t meet the scope of the problem, we throw up our hands and feel like we need to fully document how big of a problem we are facing,” Brook said. “We need to have a more robust dialogue and more options to rectify these problems on the table.”

The Office of Civil Rights has wide-ranging powers to file civil lawsuits or launch criminal investigations when constitutional rights may have been violated.

Brook said the coalition wants to see concrete changes for inmates in solitary confinement, particularly for those who are mentally ill. There should be more time given for the inmates to be outside their cells and a better procedure for identifying those with serious mental illnesses so they aren’t put in solitary confinement.

“We need some sort of outside force to push North Carolina towards a real solution to this massive problem,” Brook said.

The request comes amid renewed national interest in the conditions of solitary confinement, and its effects.

President Barack Obama spoke out on the issue in July, saying it’s not a smart correctional tool.

“Do we think it makes sense to lock so many people alone in tiny cells for 23 hours a day, sometimes for months or even years at a time?” he said. “This is not going to make us safer. This is not going to make us stronger. And if these individuals are ultimately released, how are they going to adapt? It’s not smart.”

The advocates highlighted those remarks, and also outlined mental health service gaps in the state.

Gov. Pat McCrory has requested $24 million for prison mental health services as part of his 2015-16 fiscal year budget. Since then, the state House cut that number in half as part of its budget proposal, and the Senate reduced it again.

Lawmakers are currently negotiating over a final budget.

The coalition expressed concern about the budgeting in its letter to federal officials, mentioning the Kerr case in particular.

“If $6 million is the legislative response immediately following a mentally ill inmate dying of dehydration and months of press scrutiny thereof, then the long-term prospects for addressing this crisis once the cameras have moved on are gloomy indeed,” the letter says.

The U.S. Attorney’s Office in Raleigh has opened a criminal investigation into Kerr’s death.

Thomas Walker, U.S. attorney for the Eastern District of North Carolina, said he could not discuss the status of investigation.